WORK PLANS - Laserfiche WebLink

Home Browse Search

Site Background Information: Lopez Property Page 2 of 3 of removal. Soil samples were collected and analyzed for gasoline, diesel, kerosene, motor oil, benzene, toluene, ethylbenzene, xylene (BTEX) and lead, but a chain of custody was never submitted.Although the analytical results showed non-detect for all analytes,the EHD did not close this case because of the missing chain of custody form and the discrepancy between the EHD observations and the laboratory analytical results. PREVIOUS SITE ASSESSMENT ACTIVITIES An Unauthorized Release Report(UAR)was issued by the EHD in March 1994 to facilitate further site assessment.On 04 June 1996,one soil boring was advanced through the former tank excavation to a depth of 15 feet bsg.However,the EHD was notified that the sample had been lost,and the site was resampled on 20 June 1996 at a depth of 16 feet bsg; the analytical results indicated non-detect for gasoline,BTEX and the fuel oxygenate MTBE.The laboratory quality assurance procedures were questioned by the EHD and resolved in December 1996. The property was given a "no further action" letter and"closed"by the EHD in May 1997. During a Phase I investigation for potential property transfer,a discrepancy was discovered between site maps prepared by EHD and a former consultant for the property owner. On 20 August 2003, AGE attempted to relocate the UST excavation.Field personnel located what appeared to be brackets used to secure the former UST vent pipe to a building.Based on this discovery and EHD inspection maps,a soil probe boring was advanced to a total depth of 30 feet bsg adjacent to the suspected vent pipe location to collect soil and ground water samples. Laboratory analysis of the soil samples detected total petroleum hydrocarbons quantified as gasoline (TPH-g) and BTEX compounds at maximum concentrations of 10,600 mg/kg TPH-g, 13 mg/kg benzene, 330 mg/kg toluene, 180 mg/kg ethylbenzene, and 650 mg/kg total xylenes. Laboratory analysis of the ground water sample reported 2,560,000 micrograms per liter (µg/1) TPH-g, 1,300 µg/1 benzene, 30,000 µg/1 toluene, 37,000 µg/1 ethylbenzene and 217,000 µg/1 total xylenes. MTBE was not detected in the analyzed soil and ground water samples. Three soil borings were advanced on 22 November 2004 for collection of soil samples and installation ofthree groundwater monitoring wells(MW-1,MW-2 and MW-3);the monitoring wells were developed and sampled on 24 November 2004. TPH-g was detected only in soil samples collected from boring MWI, at a maximum concentration of 2,400 mg/kg in sample MW1-20. BTEX compounds were detected only in soil samples collected from boring MW 1, at maximum concentrations of 0.19 mg/kgbenzene,73 mg/kg toluene,260 mg/kg ethylbenzene and 1,690 mg/kg xylenes in sample MW 1-20.Total lead was detected by EPA Method 6010 in soil samples collected from borings MW 1 through MW3,at a maximum concentration of 12 mg/kg(MW 1-30).The-rosu4s-� oQhe g I samples-eellooted-ori`24--Navember2%4--are°sulmnariE�ble,2"of this report. Advanced GeoEnvironmental,Inc.